1. Field of the Invention
The present invention relates to a data writing density judging apparatus and method for a disc, and in particular to an improved data writing density judging apparatus and method for a disc capable of judging a writing density of a disc by detecting an amount of cross talk which occurs when a disc track is scanned by a beam and by detecting a tracking error signal.
2. Description of the Conventional Art
Generally, the amount of data to be written on a disc of a disc reproducing apparatus is subjected to a writing density of a disc. In addition, the writing density of a disc is measured by a track pitch and a unit pit with respect to a disc track. Thus, to increase the writing density of a disc, shortening the length of a unit pit or narrowing the track pitch is necessary.
However, because of the demand for writing more data a high density disc is necessary in the industry. In a case of a reproducing apparatus adopting a low density disc, an additional apparatus is necessary for the high density disc to reduce the cost for a new reproducing apparatus for a high density disc.
Therefore, the disc reproducing apparatus needs a specific method of judging whether a high density disc or a low density disc is used.
The conventional method of judging the type of a data writing density of a disc includes an identification data (ID) code indicating a corresponding writing density in a data format of a disc. However, in this case, since there is a different density between a high density disc and a low density disc, the rotation ratio differs from each other, thus, disadvantageously increasing a time consumption to read an ID code. Also, the ID format between the high density disc and the low density disc should be disadvantageously the same.